广西茅尾海贝克喜盐草海草床硅素的分布特征

Silicon Distribution Characteristics in the Seagrass Bed of Halophila beccarii in Maowei sea, Guangxi

关键词:  硅  分布特征  海草床  贝克喜盐草  茅尾海

Key words:  silicon  distribution  seagrass bed  Halophila beccarii  Maowei sea.

摘要:

为探究海草床硅素的时空分布特征，本研究于2022年7月至2023年4月期间对广西茅尾海贝克喜盐草海草床表层沉积物的有效硅含量和贝克喜盐草的生物硅含量展开调查研究。结果表明：茅尾海海草床表层沉积物有效硅含量约为126.37 mg/kg，在空间上总体呈现由陆向海逐渐减少的变化趋势，同一站位表层有效硅含量在不同季节之间有显著差异性（P<0.05）。秋季和夏季的有效硅含量大于冬季和春季（P<0.01），秋季表层沉积物有效硅含量在不同采样站位之间有显著差异性（P<0.01）。贝克喜盐草地上组织生物硅含量（3.65±1.97 mg/g）大于地下组织（0.58±0.27 mg/g）（P<0.01），夏季生物硅含量与其他季节有显著差异性（P<0.05）。茅尾海贝克喜盐草的生物硅含量和表层沉积物的有效硅含量与环境因子之间存在不同程度的相关性，总体上呈季节性变化，且夏、秋季空间分异明显。在对该区域的贝克喜盐草种群动态进行长期监测的同时，有必要对海草生态系统硅生物地球化学循环过程进行深入研究。

Abstract:

In order to investigate the spatial and temporal distribution characteristics of silicon in seagrass beds, the available silica (ASi) content in the surface sediments and biogenic silica (BSi) content of Halophila beccarii of seagrass beds in Maowei sea were investigated from July 2022 to April 2023. The results showed that the ASi content in the surface sediments of the seagrass bed in the Maowei Sea was about 126.37 mg/kg, which showed a decreasing trend from land to sea, and the surface ASi content at the same station had a significant difference between different seasons (P<0.05). The ASi content in autumn and summer was higher than that in winter and spring (P<0.01), and the ASi content of the surface sediments in autumn was significantly different from different sampling stations (P<0.01). The mean value of the BSi content in the aboveground tissue (3.65 mg/g) was higher than that in the underground tissue (0.58 mg/g) (P<0.01), and the BSi content in summer was significantly different from that in other seasons (P<0.05). The BSi content and the ASi content of surface sediments of H. beccarii were correlated with environmental factors to varying degrees, and showed seasonal changes in general, with obvious spatial differences in summer and autumn. In addition to long-term monitoring of the population dynamics of H. beccarii in this region, it is necessary to conduct in-depth research on the biogeochemical cycle of silicon in seagrass ecosystems.